my cat is 8 years old and in the last two years she was introduced to other cats...she didn't take it very well and the other cats would eat their food so fast that they would vomit it up right away... needless to say she began doing this....and has been doing it ever since. She is now living with me and no other cats for the last 4 months but continues to throw up about 2 - 6 times a day.. the vet said that he can't find anything that is wrong with her and he suggested i take her food away for a few days... i did that and she just threw up clear... I'm not sure if this is a learned act and she has got herself in the habit of it but she seems to be a happy cat and she is somewhat social considering my parents just got a puppy about a month ago and she still comes around even though she hates the dog. I'm confused and don't know if i should put her down....I can't continue living with a sick cat.